184 The N.Z. Journal of Science and Technology. [May 
legal standards. For detecting added water the freezing-point test was 
adopted by the Dominion Laboratory after searching tests, and had proved 
most efficacious. As regards fats and total solids the Wellington milk- 
supply compared very favourably with that of a prominent London com¬ 
pany. As regards dirt, however, tested by direct observation of the sedi¬ 
ment in a glass vessel, the best Wellington samples were just within the 
American and Continental standards, and the worst had twelve times as 
much dirt. No visible sediment should be observable in a litre of milk. 
Filtering or straining was undesirable, as no dirt should ever get into the 
milk. Bacterial investigations of two kinds were carried out in the Dominion 
Laboratory. The reductase test, depending on the reduction of a solution 
of methylene blue by any bacterial ferment present, gave an idea of the 
staleness of the milk. Fermentation tests were under investigation, but 
had not so far yielded definite results. 
REVIEWS AND ABSTRACTS. 
Interim Report on the Electric-power Supply in Great Britain, 
by the Coal-conservation Sub-committee of the Reconstruction Commit¬ 
tee of the Ministry of Reconstruction. British White Paper, Cd. 8880, 
28 pp., 1917. 
This is a report addressed to the Prime Minister of Great Britain by 
Lord Haldane, Chairman of the Coal-conservation Sub-committee appointed 
by the Minister o': Reconstruction for Great Britain, and consisting of the 
Right Hon. Viscount Haldane, Charles H. Merz (Vice-Chairman), William 
A. Bone, Guy Calthrop, John Kemp, R. A. S. Redmayne, and Charles P. 
Sparks. 
The report deals, firstly, with the extent to which conservation of coal 
could effect economy in the production of motor-power and other forms 
of energy used for industrial purposes ; secondly, with the expansion of 
industry which should result in the way of new manufactures from the 
proper use of the coal so saved ; and, thirdly, with the steps necessary to 
attain these objects. 
The report contains a number of tables showing the coal raised and 
consumed in the United Kingdom, the subdivision of home consumption, 
a table from the census of production showing the extent to which output 
is dependent upon the use of power, a summary of the London electric- 
supply system, and average prices charged to consumers by electricity 
undertakings in the Lancashire area. 
The report is further accompanied by five appendices, showing the 
consumption of coal per horse-power hour for power purposes in the 
United Kingdom, a summary of electricity-supply legislation, types of 
electric-power organizations, fuel economy on the north-east coast of Great 
Britain as the result of electric-power supply, and a memorandum of the 
Association of Electric - power Companies on the electric - power - supply 
industry in the United Kingdom. 
The report is best summarized in the words of the chairman of the 
sub-committee addressed to the Right Hon. David Lloyd George, Prime 
.Minister, and of which the following is a copy 
The Coal-conservation Sub-committee have considered and given their provisional 
approval to the accompanying interim report prepared by the sub-committec which 
